You can in principle mimic laser light by simulating an electromagnetic field. Since the Lorenz force tends to be much smaller than the electric force, many people would also just simulate an electric field, which is much easier to implement.

However, before deciding how to proceed, I would start by looking if the frequency and wavelength relevant to your laser are within the accessible time and length scales in MD. Also keep in mind that such an electric field in MD is homogeneous, whereas a laser beam can be more focused.

I believe that it will be quite difficult to conduct any sort of a meaningful implementation of laser ablation directly. Unfortunately, laser light impinging on material preferentially affects the electrons: an electron feels an acceleration due to the laser field that is a thousand times greater than that of the nuclear acceleration. To include this important aspect of the problem, you will have to use a quantum description of the system. This will be much more computationally expensive. Additionally, a 1000 nm laser has a frequency of 3x10^(14) Hz. To correctly address the time-dependent behavior, you need to sample with time steps on the order of 10^(-15) s.

There are groups doing just such calculations, albeit for laser-induced fusion. Their approach is rather far afield from what is general considered MD simulations here.

This is a very interesting problem, which is typically too complex to solve by the electromagnetic or wave equation approach.

Unless you are dealing with photoablation, which typically happens with high energy photons in the UV or shorter wavelength spectrum in which laser light overcomes electronic transition and directly dissociates atoms and molecules, most laser ablation as we know it undergoes photothermal/photoacoustical/thermomechanical processes. There are however extreme cases with much complexity, such as in the case of extremely high laser irradiance > 10^12 W/cm2 where nonlinear dynamics kick in, causing optical breakdown and plasma formation - this typically happens with ultrashort laser pulses.....

For 'typical' laser ablation, I suggest starting with a Monte Carlo model, simulating laser irradiation as photon transport/migration into the material. Assuming you know the optical properties of the material, you would be able to determine the photon distribution, optical absorption, and loss (reflectance and transmittance). Time resolved optical absorption produces the source term for the heat conduction equation with which you use to calculate the temporal temperature changes. This photothermal process may or may not result in ablation. If it is below the ablation threshold, the time-temperature relation of laser interaction with the material may result in changes in its chemical or structural integrity. If it is above the ablation threshold, where local temperature rise and gradient are directly correlated to (and the source term for) mechanical stress or pressure induced within the material, one could calculate the acoustic pressure and recoil stress that may overcome the molecular bonds resulting in vaporization and dissociation (hence ablation and change in boundary condition). For short pulsed lasers operating in stress confinement, an approach to understanding this thermodynamic process may be modeled using the Grüneisen Parameter. Below are some references:

For references in Monte Carlo model, work by Jacques and Wang is well known:

Chapter Monte Carlo Modeling of Light Transport in Tissues

Chapter Monte Carlo Modeling of Light Transport in Tissue (Steady St...

Pfefer et al have studied the Monte Carlo and heat diffusion approach extensively:

Article Adaptable three-dimensional Monte Carlo modeling of imaged b...

Article Laser treatment of port wine stains: three-dimensional simul...

Article Modeling laser treatment of Port Wine Stains with a computer...

Photoacoustical process/Thermomechanical ablation:

Article Temperature dependent Grüneisen parameter

Chapter Physical Principles of Laser Ablation

Article Atomistic Modeling of Short Pulse Laser Ablation of Metals: ...

Conference Paper Inertially confined ablation of biological tissue